Photoconductors are used in a wide range of image detection and image analysis applications. For example, night vision systems employ photoconductors that are sensitive to infrared radiation.
An important measure of the effectiveness of a photoconductor is its responsivity, measured as the change in output voltage of the photoconductor divided by the optical power entering the photoconductor. With existing photoconductors, attempts at increasing the responsivity have focused on material selection and noise reduction. For example, materials such as mercury cadmium telluride are used to convert photons to electrical charge. Furthermore, cryogenically cooling such semiconductor detectors greatly reduces the noise component of the output signal. Such detectors, however, have neglected the geometric shape of the photoconductor as a factor in maximizing the photoconductor responsivity.
Therefore, a need has arisen for a method and apparatus for maximizing a photoconductor signal output through geometric shaping of the photoconductor and its charge.